Patent Literature 1 describes a heat pump apparatus including a refrigerant circuit in which a heat source unit, a use unit, and a hot water supply unit are connected with pipes.
This heat pump apparatus allows an air conditioning operation and a hot water supply operation to be independently executed in a single system, and allows the air conditioning operation and the hot water supply operation to be simultaneously executed. This heat pump apparatus makes it possible for the hot water supply unit to recover the waste heat of the use unit when the cooling operation of the use unit and the hot water supply operation of the hot water supply unit are simultaneously executed, and can achieve an efficient operation.